Patent GB-614235-A (GB)
Title: Improvements in or relating to unsaturated diesters and method of producing the same
IPC: C07C37/62
Filed: 1946-02-01
Abstract: Polymers are obtained by polymerizing unsaturated esters, which have been prepared by reacting two molecular proportions of an alkenyl chloroformate in which the alkenyl group is derived from an alkenol having a methylene group attached by a double bond to a carbon atom with a nuclear halogenated alkylidene bis-phenol, by the process of the parent Specification.  The diesters have the general formula <FORM:0614235/IV(a)/1> where R11 represents the alkenyl group, X is halogen and R and R1 represent hydrogen or alkyl groups.ALSO:Unsaturated diesters are prepared by reacting two molecular proportions of an alkenyl chloroformate in which the alkenyl group is derived from an alkenol having a methylene group attached by a double bond to a carbon atom, with a nuclear halogenated alkylidene bis-phenol.  The diesters have the general formula <FORM:0614235/IV(b)/1> wherein R11 represents the alkenyl group, X is halogen and R and R1 represent hydrogen or alkyl groups. The reaction may be effected in the presence of a strong base and/or an inert solvent and/or at a moderate temperature, preferably below about 60 DEG  C. and desirably between 0 DEG  C. to 10 DEG  C. Suitable nuclear halogenated alkylidene bis-phenols may be obtained by halogenating, e.g. by the process of Specification 491,792, bis-(4-hydroxyphenyl) methane, 2 : 2-bis-(4-hydroxyphenyl) propane, 2 : 2-bis-(4-hydroxyphenyl) butane, 2 : 2-bis-(4-hydroxyphenyl)-4-methylpentane, 2 : 2-bis-(3-methyl-4-hydroxyphenyl) propane, 2 : 2-bis-(3-phenyl-4-hydroxyphenyl) propane and 2 : 2-bis-(4-hydroxyphenyl) heptane, e.g. 2 : 2-bis-(3-chloro-4-hydroxyphenyl) propane may be prepared.  The benzene nuclei of the alkylidene bis-phenols may contain other substituents in addition to the hydroxyl and halogen groups.  The alkenyl group in the alkenyl chloroformate used may be derived from allyl, beta-allyl ethyl, beta-methyl allyl or beta-ethyl allyl alcohol or methyl-vinyl-, allyl-, ethyl-vinyl- or methyl-allyl-carbinol.  In examples, the following compounds are prepared: diallyl 2 : 2-bis-(3 - chloro - 4 - hydroxyphenyl) propane dicarbonate, 2 : 2 - bis - (3 : 5 - dichloro - 4 - hydroxyphenyl) propane dicarbonate and diallyl 2 : 2-bis - (3 : 5 - dibromo - 4 - hydroxyphenyl) propane dicarbonate.  2 : 2-Bis-(3-chloro-4-hydroxyphenyl) propane is prepared by reacting 2 : 2-bis-(4-hydroxyphenyl) propane with chlorine in glacial acetic acid solution.  The corresponding 3 : 5-dichloro compound may be similarly prepared.  2 : 2 - Bis - (3 : 5 - dibromo - 4 - hydroxy - phenyl) propane is prepared by reacting 2 : 2-bis-(4-hydroxyphenyl) propane with bromine in glacial acetic acid solution.  The Specification as open to inspection under Sect. 91 refers to the preparation of diesters of the general formula given above by reacting phosgene with a nuclear-halogenated alkylidene bis-phenol and with an alkenol having a methylene group attached by a double bond to a carbon atom, said bis-phenol and said alkenol being added in any desired sequence or simultaneously, e.g. by reacting the phosgene first with the said alkenol to form an ester of chloroformic acid which is then reacted with the said bis-phenol, or phosgene may be reacted with the said bis-phenol to form the corresponding dichloroformate which is then reacted with the required alkenol.  This subject-matter does not appear in the Specification as accepted.